This invention concerns watches which require a fast (day, month or other) correction mechanism for certain functions, in particular display functions such as a calendar (annual, perpetual, day/date, or other), or moon phase, tide, AM/PM display or other indicators. A particular example of an annual calendar mechanism is described in Patent No EP1666991B1 in the name of ETA SA.
To set the month, the user generally has to make a correction using the calendar mechanism. In the worst case, this operation may prove time-consuming and tedious. It may be that a correction of a whole year has to be made. Likewise, if the user makes a mistake during correction, the operation has to be repeated. Using the calendar mechanism to operate the correction mechanism may lead to excessive use and could result in malfunctions.
Correction mechanisms often include levers, which are essential components in timepiece movements, enabling a mechanism to switch between several different modes, in general between two distinct positions. A return spring is often provided with a timepiece lever to ensure proper motion transmission or continued bins depending on the case.
A fast correction of the month display may result in desynchronization of the system. The user then has no means of checking whether the system is synchronized, which may lead to malfunctions.